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Nieni fire, 18 January 2022 Nieni

Out · last detection 23 Jan 2022, 02:15 UTC

The fire started on 18 January 2022 in Nieni, Sierra Leone, and satellites saw it burning for 6 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 1,252 hectares from heat detections, spread across a single municipality.

It is the 668th largest in Northern since 2016 (of 1112 with a page). Number 96 in Sierra Leone in 2022, of 167.

The power measured by the satellite is low (26.4 MW in the strongest hotspot), more typical of grass or stubble burning, or a slow surface fire, than of a large crown fire.

Compare with…
Burnt area
1,252ha
GWIS perimeter (Copernicus)
Duration
6days
18 Jan 2022 – 23 Jan 2022
Municipalities hit
1
chiefdoms
Started on
18 Jan
2022
Heat detections
39
in a single hotspot: 26 MW
Average daily power
40MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 18 Jan23 Jan
23 Jan 2022

How it evolved, day by day

18 Jan 2022 · 86 MW · 9 19 Jan 2022 · 99 MW · 11 20 Jan 2022 · 43 MW · 12 21 Jan 2022 · 1 MW · 1 22 Jan 2022 · 7 MW · 4 23 Jan 2022 · 1 MW · 1
18 Jan 19 Jan 20 Jan 21 Jan 22 Jan 23 Jan

Fire radiative power detected each day, in megawatts, and number of hotspots. The magenta bar marks the peak day.

This area had burned before

76% of the perimeter overlaps earlier fires recorded since 2016: 564 ha in 2017, 916 ha in 2019. Part of it burned more than once, so the yearly figures add up to more than the 957 ha that had burned before.

How big is it?

10 km
It burned the equivalent of 0.8% of the area of London (13 km² against 1,583 km²).

London boundary: geoBoundaries · Office for National Statistics (Open Government Licence v3.0).

This compares size, not location: both shapes are at the same scale, north up, centred on each other.

What happened to each town

  1. Nieni where it started
    1,261 ha reached on 18 Jan
    0.6 %

Burnt area inside each municipality, from crossing the GWIS perimeter with administrative boundaries. The distance runs from the point marking the centre of each area to the nearest fire: staying a kilometre away does not mean it reached the houses.

People and buildings inside the perimeter

GHSL 2020
Built-up area0.53 ha
Residents≈ 150

Inside the perimeter there were about 0.53 hectares of built-up land and about 150 residents (GHSL 2020, satellite-based estimate).

This is an estimate on 100 m cells, made from satellite imagery and census data: it does not mean that homes burned or that anyone was harmed. The perimeter also contains land that never burned.

Source: Global Human Settlement Layer (GHS-BUILT-S and GHS-POP R2023A), European Commission Joint Research Centre (JRC), © European Union, CC BY 4.0. Sum inside the perimeter computed by WorldFires. human-settlement.emergency.copernicus.eu

Before and after, from space

Drag the line to compare the same ground before the fire and after it.

Before · 11 Jan 2022
After · 30 Jan 2022

If the day is cloudy, change the date: each satellite passes once a day. In false colour the burnt ground looks brown or red.

Detections table · 39Every satellite heat detection, one by one, with time, satellite, power and coordinates.
⬇ Download CSV Times in UTC. Each detection is a 375 m pixel: a large fire yields hundreds per pass.
Date and timeSatelliteFRP (MW)LatLon

Other fires nearby

All fires in Sierra Leone ›

Frequently asked questions

How long did the Nieni fire last?
GWIS (Copernicus) dates it between 18 January 2022 and 23 January 2022: 6 days between the first and last heat detection of the perimeter.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 1,252 hectares (12.5 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire only entered Nieni (1,261 ha, 0.6 %).
Where does this data come from?
From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Sierra Leone (geoBoundaries). It is not an official report.

Where to verify it

A satellite detection is not an official report. Final figures and the fire’s status are published by each country’s emergency service.

Satellite cross-check

History of this page Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.

No changes since 24 October 2026.

RSS Changes to this page

Does something look wrong on this page?

This page is built from satellite data and official records, and it sometimes gets things wrong: the wrong dates, the wrong town, two fires merged into one, or something that was not a wildfire at all. If you know this fire first-hand (you live nearby, saw it, fought it or reported on it), tell us what really happened and we will check it.

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How we know this
  • Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery.
  • Dates from the perimeter: the VIIRS detections inside it did not change them. 39 Suomi-NPP VIIRS detections on those dates.
  • We have not matched this page with any official record.
  • Built-up area and population come from the JRC Global Human Settlement Layer (epoch 2020, 100 m cells), summed inside the perimeter: an estimate of what was there, not a damage count.

How we build fire pages: methodology ›

Where this data comes from

The perimeter comes from the Copernicus Global Wildfire Information System (GWIS), which rebuilds it from MODIS and VIIRS heat detections and publishes it under CC BY 4.0. It is not measured on imagery as in Europe, so it is an estimate. Heat detections come from the VIIRS sensors aboard Suomi-NPP and NOAA-20, distributed by NASA FIRMS at 375 m resolution. Municipal boundaries come from geoBoundaries ADM3 (Creative Commons Attribution 4.0 (CC BY 4.0)). The area per municipality is computed by WorldFires by crossing the perimeter with those boundaries, so it may differ from each country’s official figure.